coreos-cloudinit: fix Equinix Metal cloudinit

This has been raised on Slack:
```
Aug 08 19:03:33 shoot-79548-jlptk bash[1678]: 2024/08/08 19:03:33 Checking availability of "packet-metadata-service"
Aug 08 19:04:03 shoot-79548-jlptk bash[1678]: 2024/08/08 19:04:03 Checking availability of "packet-metadata-service"
Aug 08 19:04:33 shoot-79548-jlptk bash[1678]: 2024/08/08 19:04:33 Checking availability of "packet-metadata-service"
Aug 08 19:05:03 shoot-79548-jlptk bash[1678]: 2024/08/08 19:05:03 Checking availability of "packet-metadata-service"
Aug 08 19:05:33 shoot-79548-jlptk bash[1678]: 2024/08/08 19:05:33 Checking availability of "packet-metadata-service"
Aug 08 19:06:03 shoot-79548-jlptk bash[1678]: 2024/08/08 19:06:03 Checking availability of "packet-metadata-service"
Aug 08 19:06:09 shoot-79548-jlptk bash[1678]: 2024/08/08 19:06:09 No datasources available in time
Aug 08 19:06:09 shoot-79548-jlptk systemd[1]: oem-cloudinit.service: Main process exited, code=exited, status=1/FAILURE
Aug 08 19:06:09 shoot-79548-jlptk systemd[1]: oem-cloudinit.service: Failed with result 'exit-code'.
Aug 08 19:06:09 shoot-79548-jlptk systemd[1]: Failed to start oem-cloudinit.service - Run cloudinit.
```

The check for metadata endpoint availability (`curl https://metadata.packet.net/`) returns a 404 so it fails.

Signed-off-by: Mathieu Tortuyaux <mtortuyaux@microsoft.com>
Signed-off-by: Jeremi Piotrowski <jpiotrowski@microsoft.com>

sdk_container/src/third_party/coreos-overlay/coreos-base/coreos-cloudinit/coreos-cloudinit-9999.ebuild

@@ -10,7 +10,7 @@ inherit git-r3 systemd toolchain-funcs udev coreos-go
 if [[ "${PV}" == 9999 ]]; then
 	KEYWORDS="~amd64 ~arm64"
 else
-	EGIT_COMMIT="f78b9f7b484497c610c8a159aa971234d384d215" # flatcar-master
+	EGIT_COMMIT="f3aaab923de5075524780716635f25564b5e6934" # flatcar-master
 	KEYWORDS="amd64 arm64"
 fi